<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        ul li{
            list-style:none;
            width:200px;
            height:100px;
            text-align:center;
            line-height: 100px;
        }
                .item1{
            background-color: rgb(77, 4, 4);
        }
        .item2{
            background-color: rgb(6, 98, 114);
        }
        .item3{
            background-color: rgb(3, 80, 33);
        }
        ul{
            display: flex;
            margin: 0;
            padding: 0;
            width: 800px;
            height:100px;
        }
        li{
            /* flex-grow: 0;
            flex-shrink: 0;*/
            flex: 1 1 200px;
        }
        /* .item2{
            flex:2;
        } */

        

        
    </style>
</head>
<body>
    <ul>
        <li class="item1">1</li>
        <li class="item2">2</li>
        <li class="item3">3</li>
    </ul>
    
</body>
</html>